1. Field of the Invention
This invention relates to a lock structure of two articles which are attached to each other.
2. Related Art
As a lock structure of two articles to be attached to each other, there is known a lock structure of connector housings (see, for example, JP-A-2001-250627 Publication).
As shown in FIG. 11, a connector 100 disclosed in Patent Literature 1 comprises two connector housings 101 and 102 stacked together in a vertical direction. The upper connector housing 101 has a downwardly-projecting lock claw 103, and the lower connector housing 102 has a lock claw 104 for engagement with the lock claw 103. An upwardly-projecting fitting protrusion 105 is formed at the lock claw 104 of the connector housing 102, and the connector housing 101 has a fitting recess 106 through which the fitting protrusion 105 can fittingly pass.
At the time of attaching the two connector housings 101 and 102 to each other, the two lock claws 103 and 104 are brought into engagement with each other by elastically deforming the lock claw 104 outwardly (in a direction of arrow A parallel to the sheet of FIG. 11). At this time, the fitting protrusion 105 is fittingly passed through the fitting recess 106, thereby preventing the lock claw 104 from excessive elastic deformation.
Incidentally, there is a tendency for external dimensions (such as a thickness) of a connector to be reduced in order to meet a recent demand for a compact design of connectors. Under the circumstances, in the connector disclosed in JP-A-2001-250627 Publication, it may be proposed to form the lock claws 103 and 104 into a thin, flattened shape. Such thin lock claws 103 and 104 are liable to be deformed in a direction of their thickness (that is, in a direction perpendicular to the sheet of FIG. 11), and therefore there is a fear that the lock claws 103 and 104 may be incompletely engaged with each other or may be broken when the lock claw is deformed in a direction different from the predetermined direction of arrow A.